Since 1993 Copyright Notice

Electron Engine ™
Printed Circuit Boards by Emissionlabs

Update:

EE24. Gold Plated Bidirectional XLR <==> RCA.

LL1527, LL1527-XL, LL1570, LL1570-XL, LL1540, LL1545, LL1578, LL581-XL.

Other small signal Boards

Introduction

This board uses 1:1 transformers, which have an attractive price. Just connect the board, and it already works. A tuning network is better, but not strictly needed.

 

• Order nr: 310-024-89
• Dimensions: 56 x 37mm

Possibilities:

Bidirectional use. Each side can be used as input or output

1. XLR INPUT: Creates a balanced, symmetric XLR INPUT to an amplifier with standard (unbalanced) RCA input. XLR1 (cable shield) of the XLR connector is normally grounded directly at the connector itself, or otherwise at the PCB.
2. XLR OUTPUT. Creates a balanced, symmetric XLR OUTPUT to an amplifier which has only an RCA output. Normally, XLR1 (cable shield) of the XLR connector is normally grounded directly at the connector itself, or otherwise at the PCB.
3. RCA and XLR INPUT in parallel. This is a special case. Connect the XLR connector just normally. For RCA connector, use an "Isolated Ground" type. Connect RCA center pin to XLR2, and RCA isolated ground to XLR3.

Grounding of the PCB

XLR1, RCA ground, PCB ground, and transformer case, are the same. (See schematic). The PCB is chassis grounded by the mounting screws. Ground of the RCA side, is soldered with a short piece directly to signal ground. .

Tuning

• If the input is RCA, use Ra and Ca.
• If the input is XLR, use Rx and Cx.

Values of Tuning resistor / capacitor. Without tuning it works also, but high frequency range is 25% lower.

		Core	Frequency Range	Distortion	Best Use	Maximum Signal	Typical Advantage
Line1	LL1527	mu-Metal	10Hz-150kHz 0.1dB	0.1% 6dbU	Input / Output	16dBU 4.89V	High frequency range at good price.
Line2	LL1527-XL	mu-Metal	10Hz-150kHz 0.1dB	0.1% 9dbU	Input / Output	19dBU 6.9V	Higher maximum signal
Line3	LL1570	Mu-Metal	10Hz-200kHz 0.5dB	0.1% 6dbU	Input / Output	16dBU 4.89V	Higher frequency range than LL1527, and higher noise immunity.
Line4	LL1570-XL	Mu-Metal	10Hz-200kHz 0.5dB	0.1% 9dbU	Input / Output	19dBU 6.9V	Higher maximum signal
Line5	LL1540	Mu-Metal	5Hz-50kHz 0.2dB	0.1% 20dBU	Input	30dBU 24.5V	High signal, low cost, low distortion. Can be used also as RCA to XLR converter.
Line6	LL1545E	Mu-Metal	5Hz-45kHz 1dB	0.2% 22dBU	Input	22dBU	Very high signal.
Line7	LL1579	Mu-Metal	10Hz-25kHz 0.5dB	0.1% 22dbU	Input	30dBU 24.5V	Very high signal. Lowest distortion of all.
Line8	LL1581-XL	Mu-Metal	10 Hz-100 kHz 0.5 dB	0.1% 3dBu 1 %	Input / Output	13dBU 3,46V	Exceptional good noise immunity.